signal.c

linux进程跟踪的工具和源代码

		printsigmask(&sigm, 0);
#ifndef USE_PROCFS
		if ((tcp->u_arg[0] & sigmask(SIGTRAP))) {
			/* Mark attempt to block SIGTRAP */
			tcp->flags |= TCB_SIGTRAPPED;
			/* Send unblockable signal */
			kill(tcp->pid, SIGSTOP);
		}
#endif /* !USE_PROCFS */		
	}
	else if (!syserror(tcp)) {
		sigset_t sigm;
		long_to_sigset(tcp->u_rval, &sigm);
		tcp->auxstr = sprintsigmask("old mask ", &sigm, 0);

		return RVAL_HEX | RVAL_STR;
	}
	return 0;
}

int
sys_sigblock(tcp)
struct tcb *tcp;
{
	return sys_sigsetmask(tcp);
}

#endif /* !SVR4 */

#ifdef HAVE_SIGACTION

#ifdef LINUX
struct old_sigaction {
	__sighandler_t __sa_handler;
	unsigned long sa_mask;
	unsigned long sa_flags;
	void (*sa_restorer)(void);
};
#define SA_HANDLER __sa_handler
#endif /* LINUX */

#ifndef SA_HANDLER                                                           
#define SA_HANDLER sa_handler                                                
#endif

int
sys_sigaction(tcp)
struct tcb *tcp;
{
	long addr;
#ifdef LINUX
	sigset_t sigset;
	struct old_sigaction sa;
#else
	struct sigaction sa;
#endif


	if (entering(tcp)) {
		printsignal(tcp->u_arg[0]);
		tprintf(", ");
		addr = tcp->u_arg[1];
	} else
		addr = tcp->u_arg[2];
	if (addr == 0)
		tprintf("NULL");
	else if (!verbose(tcp))
		tprintf("%#lx", addr);
	else if (umove(tcp, addr, &sa) < 0)
		tprintf("{...}");
	else {
		switch ((long) sa.SA_HANDLER) {
		case (long) SIG_ERR:
			tprintf("{SIG_ERR}");
			break;
		case (long) SIG_DFL:
			tprintf("{SIG_DFL}");
			break;
		case (long) SIG_IGN:
#ifndef USE_PROCFS
			if (tcp->u_arg[0] == SIGTRAP) {
				tcp->flags |= TCB_SIGTRAPPED;
				kill(tcp->pid, SIGSTOP);
			}
#endif /* !USE_PROCFS */
			tprintf("{SIG_IGN}");
			break;
		default:
#ifndef USE_PROCFS
			if (tcp->u_arg[0] == SIGTRAP) {
				tcp->flags |= TCB_SIGTRAPPED;
				kill(tcp->pid, SIGSTOP);
			}
#endif /* !USE_PROCFS */
			tprintf("{%#lx, ", (long) sa.SA_HANDLER);
#ifndef LINUX
			printsigmask (&sa.sa_mask, 0);
#else
			long_to_sigset(sa.sa_mask, &sigset);
			printsigmask(&sigset, 0);
#endif
			tprintf(", ");
			if (!printflags(sigact_flags, sa.sa_flags))
				tprintf("0");
			tprintf("}");
		}
	}
	if (entering(tcp))
		tprintf(", ");
#ifdef LINUX
	else
		tprintf(", %#lx", (unsigned long) sa.sa_restorer);
#endif
	return 0;
}

int
sys_signal(tcp)
struct tcb *tcp;
{
	if (entering(tcp)) {
		printsignal(tcp->u_arg[0]);
		tprintf(", ");
		switch (tcp->u_arg[1]) {
		case (int) SIG_ERR:
			tprintf("SIG_ERR");
			break;
		case (int) SIG_DFL:
			tprintf("SIG_DFL");
			break;
		case (int) SIG_IGN:
#ifndef USE_PROCFS
			if (tcp->u_arg[0] == SIGTRAP) {
				tcp->flags |= TCB_SIGTRAPPED;
				kill(tcp->pid, SIGSTOP);
			}
#endif /* !USE_PROCFS */
			tprintf("SIG_IGN");
			break;
		default:
#ifndef USE_PROCFS
			if (tcp->u_arg[0] == SIGTRAP) {
				tcp->flags |= TCB_SIGTRAPPED;
				kill(tcp->pid, SIGSTOP);
			}
#endif /* !USE_PROCFS */
			tprintf("%#lx", tcp->u_arg[1]);
		}
		return 0;
	}
	else {
		switch (tcp->u_rval) {
		    case (int) SIG_ERR:
			tcp->auxstr = "SIG_ERR"; break;
		    case (int) SIG_DFL:
			tcp->auxstr = "SIG_DFL"; break;
		    case (int) SIG_IGN:
			tcp->auxstr = "SIG_IGN"; break;
		    default:
			tcp->auxstr = NULL;
		}
		return RVAL_HEX | RVAL_STR;
	}
}

int
sys_sighold(tcp)
struct tcb *tcp;
{
	if (entering(tcp)) {
		printsignal(tcp->u_arg[0]);
	}
	return 0;
}

#endif /* HAVE_SIGACTION */

#ifdef LINUX

int
sys_sigreturn(tcp)
struct tcb *tcp;
{
#ifdef S390
    long usp;
    struct sigcontext_struct sc;

    if (entering(tcp)) {
	    tcp->u_arg[0] = 0;
	    if (upeek(tcp->pid,PT_GPR15,&usp)<0)
		    return 0;
	    if (umove(tcp, usp+__SIGNAL_FRAMESIZE, &sc) < 0)
		    return 0;
	    tcp->u_arg[0] = 1;
	    memcpy(&tcp->u_arg[1],&sc.oldmask[0],sizeof(sigset_t));
    } else {
	    tcp->u_rval = tcp->u_error = 0;
	    if (tcp->u_arg[0] == 0)
		    return 0;
	    tcp->auxstr = sprintsigmask("mask now ",(sigset_t *)&tcp->u_arg[1]);
	    return RVAL_NONE | RVAL_STR;
    }
    return 0;
#else
#ifdef I386
	long esp;
	struct sigcontext_struct sc;

	if (entering(tcp)) {
		tcp->u_arg[0] = 0;
		if (upeek(tcp->pid, 4*UESP, &esp) < 0)
			return 0;
		if (umove(tcp, esp, &sc) < 0)
			return 0;
		tcp->u_arg[0] = 1;
		tcp->u_arg[1] = sc.oldmask;
	}
	else {
		sigset_t sigm;
		long_to_sigset(tcp->u_arg[1], &sigm);
		tcp->u_rval = tcp->u_error = 0;
		if (tcp->u_arg[0] == 0)
			return 0;
		tcp->auxstr = sprintsigmask("mask now ", &sigm, 0);
		return RVAL_NONE | RVAL_STR;
	}
	return 0;
#else /* !I386 */
#ifdef IA64
	struct sigcontext sc;
	long sp;

	if (entering(tcp)) {
		/* offset of sigcontext in the kernel's sigframe structure: */
#		define SIGFRAME_SC_OFFSET	0x90
		tcp->u_arg[0] = 0;
		if (upeek(tcp->pid, PT_R12, &sp) < 0)
			return 0;
		if (umove(tcp, sp + 16 + SIGFRAME_SC_OFFSET, &sc) < 0)
			return 0;
		tcp->u_arg[0] = 1;
		memcpy(tcp->u_arg + 1, &sc.sc_mask, sizeof(sc.sc_mask));
	}
	else {
		sigset_t sigm;

		memcpy(&sigm, tcp->u_arg + 1, sizeof (sigm));
		tcp->u_rval = tcp->u_error = 0;
		if (tcp->u_arg[0] == 0)
			return 0;
		tcp->auxstr = sprintsigmask("mask now ", &sigm, 0);
		return RVAL_NONE | RVAL_STR;
	}
	return 0;
#else /* !IA64 */
#ifdef POWERPC
       long esp;
       struct sigcontext_struct sc;

       if (entering(tcp)) {
		   tcp->u_arg[0] = 0;
		   if (upeek(tcp->pid, 4*PT_R1, &esp) < 0)
			   return 0;
		   if (umove(tcp, esp, &sc) < 0)
			   return 0;
		   tcp->u_arg[0] = 1;
		   tcp->u_arg[1] = sc.oldmask;
       }
       else {
		   sigset_t sigm;
		   long_to_sigset(tcp->u_arg[1], &sigm);
		   tcp->u_rval = tcp->u_error = 0;
		   if (tcp->u_arg[0] == 0)
			   return 0;
		   tcp->auxstr = sprintsigmask("mask now ", &sigm, 0);
		   return RVAL_NONE | RVAL_STR;
       }
       return 0;
#else /* !POWERPC */
#ifdef M68K
	long usp;
	struct sigcontext sc;

	if (entering(tcp)) {
	    tcp->u_arg[0] = 0;
	    if (upeek(tcp->pid, 4*PT_USP, &usp) < 0)
			return 0;
	    if (umove(tcp, usp, &sc) < 0)
			return 0;
	    tcp->u_arg[0] = 1;
	    tcp->u_arg[1] = sc.sc_mask;
	}
	else {
	    sigset_t sigm;
	    long_to_sigset(tcp->u_arg[1], &sigm);
	    tcp->u_rval = tcp->u_error = 0;
	    if (tcp->u_arg[0] == 0)
			return 0;
	    tcp->auxstr = sprintsigmask("mask now ", &sigm, 0);
	    return RVAL_NONE | RVAL_STR;
	}
	return 0;
#else /* !M68K */
#ifdef ALPHA
	long fp;
	struct sigcontext_struct sc;

	if (entering(tcp)) {
	    tcp->u_arg[0] = 0;
	    if (upeek(tcp->pid, REG_FP, &fp) < 0)
			return 0;
	    if (umove(tcp, fp, &sc) < 0)
			return 0;
	    tcp->u_arg[0] = 1;
	    tcp->u_arg[1] = sc.sc_mask;
	}
	else {
	    sigset_t sigm;
	    long_to_sigset(tcp->u_arg[1], &sigm);
	    tcp->u_rval = tcp->u_error = 0;
	    if (tcp->u_arg[0] == 0)
			return 0;
	    tcp->auxstr = sprintsigmask("mask now ", &sigm, 0);
	    return RVAL_NONE | RVAL_STR;
	}
	return 0;
#else
#ifdef SPARC
	long i1;
	struct regs regs;
	m_siginfo_t si;

	if(ptrace(PTRACE_GETREGS, tcp->pid, (char *)&regs, 0) < 0) {
	    perror("sigreturn: PTRACE_GETREGS ");
	    return 0;
	}
	if(entering(tcp)) {
		tcp->u_arg[0] = 0;
		i1 = regs.r_o1;
		if(umove(tcp, i1, &si) < 0) {
			perror("sigreturn: umove ");
			return 0;
		}
		tcp->u_arg[0] = 1;
		tcp->u_arg[1] = si.si_mask;
	} else {
		sigset_t sigm;
		long_to_sigset(tcp->u_arg[1], &sigm);
		tcp->u_rval = tcp->u_error = 0;
		if(tcp->u_arg[0] == 0)
			return 0;
		tcp->auxstr = sprintsigmask("mask now ", &sigm, 0);
		return RVAL_NONE | RVAL_STR;
	}
	return 0;
#else  
#ifdef MIPS
	long sp;
	struct sigcontext sc;

	if(entering(tcp)) {
	  	tcp->u_arg[0] = 0;
		if (upeek(tcp->pid, REG_SP, &sp) < 0)
		  	return 0;
		if (umove(tcp, sp, &sc) < 0)
		  	return 0;
		tcp->u_arg[0] = 1;
		tcp->u_arg[1] = sc.sc_sigset;
	} else {
	  	tcp->u_rval = tcp->u_error = 0;
		if(tcp->u_arg[0] == 0)
		  	return 0;
		tcp->auxstr = sprintsigmask("mask now ", tcp->u_arg[1]);
		return RVAL_NONE | RVAL_STR;
	}
	return 0;
#else
#ifdef HPPA
#warning NO sys_sigreturn DECODE FOR HPPA
	return 0;
#endif /* HPPA */
#endif /* MIPS */
#endif /* SPARC */
#endif /* ALPHA */
#endif /* !M68K */
#endif /* !POWERPC */
#endif /* !IA64 */
#endif /* !I386 */
#endif /* S390 */
}

int
sys_siggetmask(tcp)
struct tcb *tcp;
{
	if (exiting(tcp)) {
		sigset_t sigm;
		long_to_sigset(tcp->u_rval, &sigm);
		tcp->auxstr = sprintsigmask("mask ", &sigm, 0);
	}
	return RVAL_HEX | RVAL_STR;
}

int
sys_sigsuspend(tcp)
struct tcb *tcp;
{
	if (entering(tcp)) {
		sigset_t sigm;
		long_to_sigset(tcp->u_arg[2], &sigm);
#if 0
		/* first two are not really arguments, but print them anyway */
		/* nevermind, they are an anachronism now, too bad... */
		tprintf("%d, %#x, ", tcp->u_arg[0], tcp->u_arg[1]);
#endif
		printsigmask(&sigm, 0);
	}
	return 0;
}

#endif /* LINUX */

#if defined(SVR4) || defined(FREEBSD)

int
sys_sigsuspend(tcp)
struct tcb *tcp;
{
	sigset_t sigset;

	if (entering(tcp)) {
		if (umove(tcp, tcp->u_arg[0], &sigset) < 0)
			tprintf("[?]");
		else
			printsigmask(&sigset, 0);
	}
	return 0;
}
#ifndef FREEBSD
static struct xlat ucontext_flags[] = {
	{ UC_SIGMASK,	"UC_SIGMASK"	},
	{ UC_STACK,	"UC_STACK"	},
	{ UC_CPU,	"UC_CPU"	},
#ifdef UC_FPU
	{ UC_FPU,	"UC_FPU"	},
#endif
#ifdef UC_INTR
	{ UC_INTR,	"UC_INTR"	},
#endif
	{ 0,		NULL		},
};
#endif /* !FREEBSD */
#endif /* SVR4 || FREEBSD */

#if defined SVR4 || defined LINUX || defined FREEBSD
#if defined LINUX && !defined SS_ONSTACK
#define SS_ONSTACK      1
#define SS_DISABLE      2
#if __GLIBC_MINOR__ == 0
typedef struct
{
	__ptr_t ss_sp;
	int ss_flags;
	size_t ss_size;
} stack_t;
#endif
#endif
#ifdef FREEBSD
#define stack_t struct sigaltstack
#endif

static struct xlat sigaltstack_flags[] = {
	{ SS_ONSTACK,	"SS_ONSTACK"	},
	{ SS_DISABLE,	"SS_DISABLE"	},
	{ 0,		NULL		},
};
#endif

#ifdef SVR4
static void
printcontext(tcp, ucp)
struct tcb *tcp;
ucontext_t *ucp;
{
	tprintf("{");
	if (!abbrev(tcp)) {
		tprintf("uc_flags=");
		if (!printflags(ucontext_flags, ucp->uc_flags))
			tprintf("0");
		tprintf(", uc_link=%#lx, ", (unsigned long) ucp->uc_link);
	}
	tprintf("uc_sigmask=");
	printsigmask(ucp->uc_sigmask, 0);
	if (!abbrev(tcp)) {
		tprintf(", uc_stack={ss_sp=%#lx, ss_size=%d, ss_flags=",
			(unsigned long) ucp->uc_stack.ss_sp,
			ucp->uc_stack.ss_size);
		if (!printflags(sigaltstack_flags, ucp->uc_stack.ss_flags))
			tprintf("0");
		tprintf("}");
	}
	tprintf(", ...}");
}

int
sys_getcontext(tcp)
struct tcb *tcp;
{
	ucontext_t uc;

	if (exiting(tcp)) {
		if (tcp->u_error)
			tprintf("%#lx", tcp->u_arg[0]);
		else if (!tcp->u_arg[0])
			tprintf("NULL");
		else if (umove(tcp, tcp->u_arg[0], &uc) < 0)
			tprintf("{...}");
		else
			printcontext(tcp, &uc);
	}
	return 0;
}

int
sys_setcontext(tcp)
struct tcb *tcp;
{
	ucontext_t uc;

	if (entering(tcp)) {
		if (!tcp->u_arg[0])
			tprintf("NULL");
		else if (umove(tcp, tcp->u_arg[0], &uc) < 0)
			tprintf("{...}");
		else
			printcontext(tcp, &uc);
	}
	else {
		tcp->u_rval = tcp->u_error = 0;
		if (tcp->u_arg[0] == 0)
			return 0;
		return RVAL_NONE;
	}
	return 0;
}

#endif /* SVR4 */

#if defined(LINUX) || defined(FREEBSD)

static int
print_stack_t(tcp, addr)
struct tcb *tcp;
unsigned long addr;
{
	stack_t ss;
	if (umove(tcp, addr, &ss) < 0)
		return -1;
	tprintf("{ss_sp=%#lx, ss_flags=", (unsigned long) ss.ss_sp);
	if (!printflags(sigaltstack_flags, ss.ss_flags))
		tprintf("0");
	tprintf(", ss_size=%lu}", (unsigned long) ss.ss_size);
	return 0;
}

int
sys_sigaltstack(tcp)
	struct tcb *tcp;
{
	if (entering(tcp)) {
		if (tcp->u_arg[0] == 0)
			tprintf("NULL");